Linking home environments and primary care: Obesity prevention for 2-4 year olds Obesity prevention for at-risk preschool children is a public health priority. The pediatric primary care setting is a relatively untapped resource for initiating obesity prevention efforts and providing recommendations and support to families for creating home environments conducive to healthy growth. The goals of this developmental (R21) study are to develop and evaluate the feasibility and acceptability of a primary care- based, preschool obesity prevention intervention integrating pediatrician counseling and a home-based program for parents of 2-4 year old children at risk for obesity. To achieve this goal, we will identify and recruit 60 eligible parent-child dyads from families of 2-4 year old at risk children defined as having a BMI between the 85th and 95th percentile for age and gender or a BMI between the 50th and 85th percentile and at least one overweight parent. These dyads will be randomized to one of the following conditions: (a) Healthy Eating/Physical Activity Home-based Intervention including brief pediatrician counseling regarding the child's current BMI percentile status, recommendations for home environmental changes to achieve a healthy weight gain trajectory, and home safety and injury risk reduction environmental recommendations paired with a 6 month home-based program delivered via phone by a masters-level health behavior specialist to promote implementation of the obesity prevention home environmental strategies, or (b) General Health/Safety/Injury Prevention Home-based Contact Control Intervention: Families will receive the same brief counseling from their pediatrician paired with a 6 month home-based program delivered via phone by a masters-level health behavior specialist to promote implementation of the general health, safety and injury prevention home environmental strategies. Primary goals of this R21 are to assess the feasibility, acceptability, and potential efficacy of the intervention. We will estimate intervention impact on diet, activity level, hypothesized mediators of BMI change, and BMI. Our study setting is ideal given our expertise in phone-based obesity interventions and access to a pediatric primary care population and associated health information systems. If successful, this approach will be evaluated on a larger scale and provide a potential model for addressing one of the most important public health challenges of the 21st century. PUBLIC HEALTH RELEVANCE: This R21 study will develop and test the feasibility and acceptability of a primary care-based obesity prevention intervention that integrates counseling by pediatric primary care providers and a home-based program for parents of 2-4 year old children at risk for obesity. The home-based program is delivered by phone and will help parents create a healthy home environment to encourage healthy eating and activity patterns and healthy weight gain in their preschool age children.